The problem is estimating the length of a book in the library that is unopened. The actual length depends on the formatting and layout settings that wouldn't have been applied yet. Overnight for opened books that have formatting applied, the overall length is a rough approximation.

Regarding the white dots/blue dots idea, that's not too difficult to do, and coming to think of it, very cool. I can fit it into the January update.

Rough (even very rough) estimates are perfectly fine for the Library view! No one would be counting the precise number of dots, anyway, and if that number of dots changes between before and after first opening a book, so what? A rough, preliminary estimate (you could even say, guess) is still better than no length indication, in my opinion.

If Marvin can't see data such as the number of words in the book before actually opening the book for the first time, you could instruct Marvin to simply use the number of kilobytes in a file to decide on the preliminary number of dots. Naturally, that's imprecise because it doesn't take into account the book's formatting, presence of any images, etc., but it definitely seems better than having no educated guess at all. The numeric progress indicator would be at the precise 0%, of course, the book as yet being unopened. But you might decide, say, that an EPUB file of 500 kilobytes would by default get the full row of 25 dots, while a file of 150 kilobytes size would only get 8 dots, etc. Once a book gets opened for the first time, the number of dots would be adjusted depending on (for example) the number of actual words in the book.

"Guestimating" the size of the book before opening it and displaying pretty much useless and completely inaccurate data seems worse to me (and detrimental to the user experience) than having no size indication at all.

Displaying the size in Kb or something won't help either since, as you said yourself, images, etc. will make that vary greatly between books.

Well, OK, Wulf. Could we then, perhaps, agree on the following behaviour as the most rational and most useful?

If a book has not been opened yet in Marvin, display no dots at all, and no numeric progess indicator yet (does not make sense for unopened books), and display only the New tag.

Once a book gets opened for the first time, display the number of dots relative to the approximate overall length of the book (the more dots, the longer the book), with 2 contrasting dot colours (or shapes) indicating the reader's progress inside the book, in addition to the numeric progress indicator.

(To me, there would be little difference between the 2 scenarios, because I typically don't leave books unopened in Marvin for a very long time, if any time at all. I mean, why would I load books into Marvin in the first place, if I never bothered to open them? The cloud = Calibre folders, rather than Marvin, is my long-term books repository.)

PS: Nice screenshots, Kris, except that they suggest that Crime and Punishment and Heart of Darkness are as if of equal length, although (as we know) the first is a mamooth novel, and the second a slim volume. If you only displayed the dots after a book actually gets opened for the first time, you might adjust the number of dots to correspond to the approximate length of a book, as proposed above.

Well, Alexander, personally, I agree with either of those two approaches but it's Kris' "baby" and he probably saw both our arguments and will decide what he likes best.

(As for the leaving books unopened for long - same here. The other night, I read a book till 2:30 am because I just "had" to finish it And, as you know, I'm a staunch supporter of using the cloud to store ebooks instead keeping tons of ebooks in the ebook reader.)

I think it is very interesting to know how big a book is relative to another so this is something that I will actively investigate. It's just that I haven't found a way yet. Maybe I'll have "a moment of clarity" after this evening's party

Hmmm... but there must be a way, right? Otherwise, there would be no way to get at the value of the numeric progress indicator. If it says (for example) 5%, then there must be a value corresponding to 100%... and you could use whatever corresponds to 100% to decide about the number of dots to show for a book. As mentioned, a very rough estimate would do for the Library view, and I don't see why the number of dots displayed could not be (slightly) re-adjusted between readings (book openings), if necessary.